a loupe is a good thing for any beginner to use for indicating harvest time.
some people recommend buying a 30x for beginners, but its not that great.
if ur gonna get a 30x loupe, get a 60x or better yet a 100x loupe to go with it.
they whole point of a loupe when identifying trichome stages is to see clearly up-close INTO individual trichomes. which a 100x times does MAGNIFIcently. (lol pun intended)
a 30x just zooms into the bud so that it looks sparkly like a high times photo.
oh and get a loupe with a nice bright, blue light
and BTW ur plants look kinda crispy. u got any kind of a fan blowing on that plant?
if u dont have a fan, keep the lights about 6-8 inches away (this sucks because flourescent lighting loses its lumen intensity drastically when placed further than about 3-4 inches)
if u do have a fan, then um.. cut a hole in whatever it is that ur growing the plant in cuz there is no ventilation at all lol
hope this helps.